The invention generally relates to an apparatus to make appropriately shaped masonry or foam building blocks for arranging and setting in courses or layers--masonry style--to build a blockwork domed structure therefrom, as well as relating to, a method of making or cutting an individual block from a billet of masonry or foam raw stock material (e.g., foam such as polystyrene and the like), and also, the resultant domed structure.
U.S. Pat. Nos. 4,155,967 and 4,324,074--South et al., disclose a domed building structures and a method of making them. More particularly, those patent references disclose a dome building constructed by a process deploying spray-gun applied urethane and concrete (available at least under one brand name as SHOTCRETE.TM.). The process involves pouring a ring foundation. If the dome is small the ring foundation and the circular base floor can be poured at once. Otherwise the circular base floor can be poured later. Steel hooks are embedded in the ring portion of the foundation. A fabric-walled bubble or membrane is attached to the ring foundation and inflated by fans. The fabric-walled membrane is scaled to and given the shape that is ultimately desired for the completed building. Hence the fabric-walled membrane serves as the form for the building during construction.
Next a coating of polyurethane foam is applied to the inside surface of the fabric-walled membrane via use of pressurized-spray equipment. The polyurethane-foam coating is built to a thickness of approximately three inches (8 cm) thick, and allowed to dry. The fans and a double-door airlock maintain pressure inside while the foam dries. Following that, steel reinforcing bar is hung on the foam and anchored to the hooks in the ring foundation. And after that, another coating is applied from the inside, this time it being the SHOTCRETE.TM. or the like. The concrete is allowed to set. The dome is thus complete. The fabric-walled membrane is left in place for forming a single-ply water-proofing membrane on the roof of the structure.
Domes constructed as described have proved popular in various applications including foremost among the applications as residential dwellings. One of the more attractive utilitarian features of these dome homes is their energy efficiency. The foam layer that extends three inches (8 cm) thick provides an effective R-value in excess of a whopping value of 60. There are anecdotal reports that a foam-dome residence in Texas was sufficiently heated during the winter by the equivalent of two hair dryers. Regardless, foam-dome building sites have ranged from the Equator to the Arctic Circle and northward particularly because of the economy they provide for cooling and/or heating. Also, the concrete inner layer acts as a heat sink for the inside temperature of the home, receiving and releasing the ambient temperature over time and hence smoothing out fluctuations.
Additionally, the stream-lined low profile of many of the dome homes has caused them more likely to survive a direct coastal hurricane assault than other home styles. Utilitarian features aside, homeowners of dome residences simply prefer its aesthetic qualities too, including how a dome profile attractively graces the natural environment.
There are shortcomings with the prior art method of producing a dome building. The profile of the building is limited to whatever shape can be inflated via an inflatable membrane. The thickness of the foam coating has a practical limit of whatever will adhere to and harden on the membrane without unduly flowing. Also, the uniformity of the thickness of the foam coating is susceptible to the same problems. What is needed is an improvement which overcomes the shortcomings of the prior art.
It is an object of the invention to provide an appropriately shaped masonry or foam building block for arranging and setting in courses or layers--masonry style--to build a blockwork domed structure therefrom.
It is an alternate object of the invention to provide a method of making or cutting an individual block from a billet of masonry or foam raw stock material.
It is another object of the invention to produce the resultant blockwork domed structure from the foregoing blocks.
A number of additional features and objects will be apparent in connection with the following discussion of preferred embodiments and examples.